Image calibration method and image calibration device

Abstract

To alleviate the strictness degree required for a relative positional relationship between a calibration index and a vehicle in an image calibration method and an image calibration device. The image calibration device includes a calibration index, four cameras, a distortion correction processing unit, a viewpoint transformation processing unit, and a calibration processing unit. The calibration indexincludes two mutually parallel lines and a distance between which is known and one line orthogonal to the two lines. The camerastake peripheral area images Sto Sof peripheral areas Rto Rincluding the calibration index. The distortion correction processing unitcorrects the peripheral area images Sto Sby using internal parameters M to obtain distortion-corrected images Pto P. The viewpoint transformation processing unitperforms viewpoint transformation processing on the distortion-corrected images Pto Pby using external parameters N to obtain a viewpoint-transformed composite image Q. The calibration processing unitperforms calibration in the viewpoint transformation processing. The calibration processing unitincludes an internal parameter correction unitand an external parameter correction unit. The internal parameter correction unitcorrects the internal parameters M. The external parameter correction unitcorrects the external parameters N.